Aquatic macroinvertebrate biodiversity: patterns and surrogates in mountainous Spanish national parks

In Spain, national parks represent the mainstay of conservation polices and attempt to protect the most representative natural ecosystems. However, studies on the ecology and conservation of aquatic biodiversity within protected areas are still scarce. This study aimed at compiling an inventory of the macroinvertebrate families inhabiting the aquatic ecosystems of each mountainous Spanish national park (Sierra Nevada, Cabaneros, Ordesa, Picos de Europa, Aiguestortes and Monfrague). The results were used to answer two questions: (i) Which environmental variables are related to macroinvertebrate composition and richness in these protected ecosystems? (ii) Which taxon or group of taxa could act as biodiversity surrogates? Sampling was carried out in 81 aquatic ecosystems across the six national parks during the summers of 2008-2010. The national parks with the highest richness were Picos de Europa and Cabaneros. Overall, the six parks incorporated 66.2% of the taxa included in the Iberian checklist. Multivariate techniques showed that maximum altitude and the presence of lotic habitats were the most important variables related to different community compositions. The best richness model included the presence of a lotic habitat, together with the percentage of the catchment area with non-irrigated agriculture and siliceous geology. Selecting several diverse lotic and lentic water bodies at different altitudes provides the best way of representing Iberian macroinvertebrate diversity. Coleoptera family richness may be used as a macroinvertebrate biodiversity surrogate in Iberian mountainous protected areas because it displayed the highest correlation with the other taxonomic groups and remaining richness values. Such an indicator could be complemented with the use of Odonata family richness for standing waters. The adequacy of Coleopera and Odonata as biodiversity surrogates should be tested at a wider geographic scale, and other surrogacy concepts (e.g. community composition) considered for assessing the role of this network in the protection of rare and endemic species. Copyright (c) 2012 John Wiley & Sons, Ltd.